// echrome04.c // compile: gcc -o echrome04 echrome04.c -lgd -lpng -lm // // Plating and unplating an electrochromic thruster #define NAME "echrome04" #define RATE 10 #define FNT "DejaVuMonoSans" #define FSZ 20 // this scales the font and the whole drawing #define NPICS 50 // #define LINETHICK 1 #define XSIZE (60*FSZ) #define YSIZE (32*FSZ) #define WIDE ( 2*FSZ) #define TALL (16*FSZ) #define XCENT (30*FSZ) #define YCENT (16*FSZ) #define ITILT 0.18 #define ASIZE 2 #include #include #include #include #include #include #define PI 3.14159265359 #define DEG2RAD(x) ((x)*PI/180.) // ---------------------------------------------------- char rmmkdir[200] ; char pngfmt[ 200] ; double ffrac ; // frame fraction int sign ; // sign of battery gdImagePtr im; int ytop= YCENT - TALL/2 ; int ybot= YCENT + TALL/2 ; int deltay = (int)( ((double)ITILT)*((double)XCENT) ) ; int black, white, gray ; int red, lred ; int green, lgreen ; int sun1, dgray, trans ; int light[256] ; // Yellow color range int light1 ; double pi2 ; // double atom[1000] ; //====================================================================== //---------------------------------------- void atom_init() { int y ; for( y=ytop ; y<= ybot ; y += ASIZE ) { atom[y]=drand48() ; } } //---------------------------------------- void frame_init() { im = gdImageCreateTrueColor(XSIZE, YSIZE); white = gdImageColorAllocate (im, 255, 255, 255); black = gdImageColorAllocate (im, 0, 0, 0); gray = gdImageColorAllocate (im, 127, 127, 127); dgray = gdImageColorAllocate (im, 64, 64, 64); red = gdImageColorAllocate (im, 255, 0, 0); green = gdImageColorAllocate (im, 0, 255, 0); lred = gdImageColorAllocate (im, 255, 224, 224); lgreen = gdImageColorAllocate (im, 224, 255, 224); sun1 = gdImageColorAllocate (im, 0, 51, 102); trans = gdImageColorAllocate (im, 1, 1, 1); } //---------------------------------------- void light_init() { int i ; int rx, gx, bx ; double di ; for( i=0 ; i < 256 ; i++ ) { di = (double) i ; int rx = (double)( di ) ; int gx = (double)( 51.0 + (204.0/256.0) * di ) ; int bx = (double)( 102.0 - (102.0/256.0) * di ) ; // printf( "%3d%4d%4d%4d\n", i, rx, gx, bx ); light[i] = gdImageColorAllocate( im, rx, gx, bx ) ; } sun1 = light[0] ; light1 = light[255] ; } //---------------------------------------- void draw_background() { gdImageFilledRectangle( im, 0, 0, XSIZE-1, YSIZE-1, sun1 ); } //---------------------------------------- void draw_light() { int light01 = light[ 127 ] ; // gamma is funny, so this corrects additive light int light02 = light[ ((int)(127.0 * (1.0+0.3*sqrt(ffrac)))) ] ; int light03 = light[ ((int)(127.0 * ffrac )) ] ; int light04 = light[ ((int)(127.0 * (1.0-ffrac))) ] ; gdPoint alight[8] ; // incoming triangle alight[0].x = 0 ; alight[0].y = ytop - deltay ; alight[1].x = 0 ; alight[1].y = ytop + deltay ; alight[2].x = XCENT ; alight[2].y = ytop ; gdImageFilledPolygon( im , alight, 3 , light01 ) ; // reflected addition alight[0].x = 0 ; alight[0].y = ytop + deltay ; alight[1].x = 0 ; alight[1].y = ybot - deltay ; alight[2].x = XCENT ; alight[2].y = ybot ; alight[3].x = XCENT ; alight[3].y = ytop ; gdImageFilledPolygon( im , alight, 4 , light02 ) ; // reflected triangle alight[0].x = 0 ; alight[0].y = ybot + deltay ; alight[1].x = 0 ; alight[1].y = ybot - deltay ; alight[2].x = XCENT ; alight[2].y = ybot ; gdImageFilledPolygon( im , alight, 3 , light03 ) ; // passthrough alight[0].x = XSIZE-1 ; alight[0].y = ytop + deltay ; alight[1].x = XSIZE-1 ; alight[1].y = ybot + deltay ; alight[2].x = XCENT ; alight[2].y = ybot ; alight[3].x = XCENT ; alight[3].y = ytop ; gdImageFilledPolygon( im , alight, 4 , light04 ) ; } //---------------------------------------- void draw_sun() { gdImageFilledRectangle( im, 0, ytop-deltay, 10, ybot-deltay , light1 ); } //---------------------------------------- void draw_atoms() { int y ; double a = 0.5+(double) XCENT ; double f = ((double)(WIDE-ASIZE))*(1.0-ffrac) ; for( y=ytop ; y< ybot ; y += ASIZE ) { int x = (int)(a+f*atom[y]) ; gdImageFilledRectangle( im, x, y, x+ASIZE, y+ASIZE, white ); } } //---------------------------------------- void draw_frame() { int ffx, fx1, fx2, ffy, fww, fw2, xcc ; int yb1, yb2, yb3, yb4, yb5 ; int xb0, xb1, xb2, xb3, xb4, xb5 ; int xc0, xc1, xc2, xc3, xc4, xc5 ; int yc1, yc2 ; ffx = (int) FSZ ; fx1 = (int) (0.7*FSZ) ; fx2 = (int) (0.5*FSZ) ; ffy = (int) (0.7*FSZ) ; fww = (int) (WIDE) ; fw2 = (int) (WIDE/2) ; xcc = (int) (XCENT) ; // printf( "%5d %5d %5d %5d %5d %5d\n", ybot, xcc, ffx, ffy, fx2, fw2 ); yb1 = ybot + ffy ; yb2 = ybot + 2 * ffy ; yb3 = ybot + 3 * ffy ; // center yb4 = ybot + 4 * ffy ; yb5 = ybot + 5 * ffy ; xb0 = xcc - fw2 ; xb1 = xcc + fw2 - fx1 ; xb2 = xb1 + fx2 ; xb3 = xb2 + fx2 ; xb4 = xb3 + fx2 ; xb5 = xcc + fw2 * 3 ; xc0 = xcc - 2*fww ; xc1 = xc0 + ffx ; xc2 = xc1 + ffx ; xc3 = xcc + 3*fww ; xc4 = xc3 - ffx ; xc5 = xc4 - ffx ; yc1 = yb3 - ffx ; yc2 = yb3 + ffx ; // printf( "%5d %5d %5d %5d %5d %5d %5d %5d %5d %5d %5d\n", // xb0,xb1,xb2,xb3,xb4,xb5, yb1,yb2,yb3,yb4,yb5 ); gdImageSetThickness( im, 3 ); gdImageRectangle( im, xcc-fww, ybot, xcc , ytop, white ); gdImageRectangle( im, xcc+fww, ybot, xcc+2*fww, ytop, white ); // battery gdImageSetThickness( im, 5 ); gdImageLine( im, xb0, ybot, xb0, yb3, white ); gdImageLine( im, xb0, yb3, xb1, yb3, white ); gdImageLine( im, xb1, yb1, xb1, yb5, white ); gdImageLine( im, xb2, yb2, xb2, yb4, white ); gdImageLine( im, xb3, yb1, xb3, yb5, white ); gdImageLine( im, xb4, yb2, xb4, yb4, white ); gdImageLine( im, xb5, yb3, xb4, yb3, white ); gdImageLine( im, xb5, ybot, xb5, yb3, white ); gdImageSetThickness( im, 7 ); if( sign == 0 ) { gdImageLine( im, xc0, yb3, xc2, yb3, green ); gdImageLine( im, xc1, yc1, xc1, yc2, green ); gdImageLine( im, xc3, yb3, xc5, yb3, red ); } else if( sign == 1 ) { gdImageLine( im, xc0, yb3, xc2, yb3, red ); gdImageLine( im, xc4, yc1, xc4, yc2, green ); gdImageLine( im, xc3, yb3, xc5, yb3, green ); } gdImageSetThickness( im, 1 ); } //===================================================================== int main () { FILE *pngout ; char comment[80] ; char dirname[80] ; char framename[80] ; int frame ; // frame count int npics ; // last frame count int i ; pi2 = 8.0*atan(1.0) ; // pi npics = (double)NPICS ; sprintf( rmmkdir, "rm -rf %sdir ; mkdir %sdir", NAME, NAME ); system( rmmkdir ) ; // make directory atom_init() ; // set up atom points for( frame = 0 ; frame <= npics ; frame++ ) { printf( "%04d/%04d\r", frame, npics ); fflush( stdout ); frame_init() ; // set up colors light_init() ; // sinusoidal fraction variation ffrac = 0.6*(0.8333-cos( pi2*((double)frame)/npics )); if( ffrac < 0.0 ) { sign=-1 ; ffrac=0.0 ; } else if( ffrac > 1.0 ) { sign=-1 ; ffrac=1.0 ; } else if( frame < NPICS/2 ) { sign= 1 ; } else { sign= 0 ; } draw_background() ; // draw sunw background draw_light() ; // draw light draw_sun() ; // draw sun draw_atoms() ; // draw atoms draw_frame() ; // draw frame and battery /* gdImageStringFT( im, NULL, white, FNT, 1.5*FSZ, 0.0, // TITLE (int)(2.0*FSZ), (int)(2.0*FSZ), "Electrochromic Light Shutter" ); gdImageStringFT( im, NULL, black, FNT, 0.7*FSZ, 0.0, // TITLE (int)(XCENT+3*WIDE), YSIZE-(int)( 0.5*FSZ), "Polarity(?)" ); */ sprintf( framename, "%sdir/a%04d.png", NAME , frame ); pngout = fopen ( framename , "wb"); gdImagePngEx( im, pngout, 1 ); gdImageDestroy (im); fclose (pngout); } // end of frame loop }